Things to Note for EFI Bikes.

[Baal]

http://answers.yahoo.com/question/index?qid=20100408130854AA9m3zH

 

 

Problems you could encounter

The engine does not take as well to modifications or aftermarket parts

A simple air filter upgrade or different mufflers can cause all sorts of problems.

Must be tuned via a tuner, usually by the dealer or a professional motorcycle mechanic.

More complicated than a carburetor. When they work, they work well. When they don't work, they can be a nightmare, even for a professional or the dealer.

 

True story. I won't mention the make. A person added some aftermarket pipes and an aftermarket air filter to his new fuel injected bike. In a very short time, within a couple of miles, the computer detected these changes as a fault and switched into a limp home mode. The engine still ran, but ran like crap. The person needed to go to the dealer and get the computer reprogrammed. Got expensive fast. He didn't know that you needed an aftermarket tuner added before you added any other aftermarket parts.

 

 

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http://www.autoevolution.com/news/motorcycle-dilemma-carbureted-vs-fuel-injected-23635.html

 

Carb problems can be fixed with basic tools on the side of the road⌕ Carb problems can be fixed with basic tools on the side of the road

Probably one of the most controversial discussions among motorcycle enthusiasts is the difference between carbureted and fuel injected bikes, as each of them has its own avid supporters. For some beginners, this is a small detail that it’s not even worth giving it a thought, as they usually choose a bike depending on other aspects, such as the price, the power, the weight or just the brand.

 

Most experimented riders, however, will put this on top of their list when it comes to make a decision regarding their next two-wheeled ride. However, one thing is for sure: once you find out the differences between the two, you must couple this to other details such as how you ride, where you live, what temperatures you ride at, and so on.

 

Many motorcycles still utilize carbureted engines, though all current high-performance designs have switched to fuel injection. However, one advantage a carb has over fuel injection is that most mechanics have worked with carbs and far fewer have any experience at all with fuel-injection systems. Old bikers would also stick to their carbureted option, as they are simpler to maintain and repair. However, while fuel injection generally increases the cost of the bike, it also provides much better cold starting, better throttle response, better fuel efficiency, less maintenance.

 

The first thing you’ll hear at a debate on carb versus fuel injected bikes is cold starts. Carbureted motorcycles need some time until they are ready to hit the road at low temperatures. The choke system is used to start cold engines. Since the fuel in a cold engine is sticking to the cylinder walls because of condensation, the mixture is too lean for the engine to start. The choke system will add fuel to the engine to compensate for the fuel that is stuck to the cylinder walls. Once the engine is warmed up, condensation is not a problem, and the choke is not needed anymore.

 

 

Fuel injected bikes usually require replacing parts⌕ Fuel injected bikes usually require replacing parts

On the other hand, what most riders like about fuel injected engines is that cold starts are much more simpler. No choke or carb adjustment, all you have to do is turn the key and hit the start button. From a mechanical perspective, the thing with fuel injected rides are far more complex. There is a fuel pump in the tank, an electronic engine controller and multiple sensors.

 

A fuel injected system is a computer controlled fuel delivery system. The ECU reads various sensors located on the vehicle and makes the determination of how much fuel to allow the engine to have based on this information. The computer will open and close the injectors allowing gasoline into the engine based on the sensor inputs and the fuel map programmed into the computer. The various sensors (RPM, engine temperature, air temperature, throttle position, manifold pressure, crankshaft position) provide information on operating conditions and load on the engine.

 

A carburetor is a demand device dependent upon the velocity of the air entering the venturi to create the air/fuel mixture that feeds the engine, and also maintains a series of fuel circuits to help maintain the best possible fuel mixture. The ability of a carburetor to provide a good air/fuel mixture is very dependent upon the velocity of the air going through it.

 

With an electronic fuel injection system, the required fuel amount for each RPM and engine load condition is located in the fuel map located in the ECU. Once this primary fuel amount is known, the ECU further adjusts the fuel mixture for the engine and air intake temperatures. In many cases, the mixture will even be adjusted for the barometric pressure and altitude.

 

While carb problems can usually be fixed on the side of the road with basic tools, EFI problems usually require replacing parts.

 

 

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http://motormag.net/2012/01/top-5-signs-of-a-bad-fuel-injector/

 

 

Top 5 Signs of a Bad Fuel Injector

 

 

10 January 2012

 

 

Fuel injectors when fail can lead to a bunch of problems that can affect the engine performance. Nobody would love to come across such a snag, especially for those who have experienced the hefty repair charges from their local mechanics. There’s no substitute for replacement if the fuel injector is really bad. However, you can save other parts of the engine from getting damaged, if you manage well enough to look for the striking signs, which point towards a failing fuel injector. Here’s a list of the 5 most known signs that indicate a bad fuel injector.

 

Abrupt Engine Power

 

It is easy to understand that when a fuel injector is clogged, the fuel supply will be irregular too. With such lopsided flow, the engine will fluctuate between low and high rpm’s causing it to deliver the power in chunks, rather than being smooth and gradual.

 

Engine Misfire

 

In case when the injector keeps on struggling against the clogging of foreign particles, a time may come when it might miss out to supply the fuel completely when it is required to. Thus, the engine results to give a compromising performance. The engine will misfire which can be felt easily while driving. This is really a bad sign and requires immediate response because misfire would give rise to engine overheating and pre-igniting the fuel mixture.

 

 

Rough Idle

 

Damaged fuel injector will not only give weird problems while on the go, the effects will persist even when the engine is running idle. Instead of a smooth engine idle, it will be rough and irregular when the fuel supply is abrupt.

 

 

 

Leaking Fuel

 

Apart from those internal chokes, fuel injectors can turn out to be bad even due to external cracks developed on the exterior body part of the injector. This damage is common for those injectors fitted on to the intake manifold. These cracks can cause the fuel to leak from the body, rather than flowing through the nozzle, which can be seen and smelled easily. The leaking fuel, instead of being sprayed in atomized form, flows in the manifold in the form of droplets. This will cause the air fuel mixture to turn out

weak, giving out poor engine efficiency.

 

Reduced Gas Mileage

 

It is obvious, that a damaged fuel injector would either cause the fuel to be wasted by leaking from the body or would supply excessive fuel when the internal springs are damaged. These conditions will undoubtedly lead the car engine to run poor reducing the gas mileage.

 

Watch out for these most common signs in your car if you are suspecting the fuel injector to be faulty. Responding to these problems early can save a great amount of time and money and can also avoid damaging to other parts. Pay attention today itself and keep yourself away from paying extra for your auto repairs.

 

 

 

Author: John is a passionate auto expert aiming towards keeping the auto repairs simple and effective at no extra cost. He is sharing his best knowledge on nissan fuel injectors replacements.

Edited November 8, 2013 by Baal